One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to determine when to plant hibiscus by reviewing the USDA zone info for San Ramon.

Planting Calendar for Hibiscus

Frost tolerance for hibiscus:	Not tolerant of frost.
When to plant:	After the last frost.

Since hibiscus are not cold tolerant it is necessary to wait until after the last frost before you can plant them.

The earliest that you can plant hibiscus in San Ramon is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant hibiscus and expect a good harvest is probably September. You probably don't want to wait any later than that or else your hibiscus may not have a chance to really do well. Starting your hibiscus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In San Ramon the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 25°F.

Since the USDA zone info for San Ramon is not always accurate the actual date of last frost will vary from year to year. Half of the time in San Ramon last frost occurs after February 15 so just be sure to be ready to cover your hibiscus in the event of a surprise late frost.

USDA Zone Info for San Ramon

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in San Ramon

You may be interested in your other planting guides for San Ramon.